The invention relates to a process for providing markings, in particular printing, on blanks for the production of packs, the blanks being severed from a continuous material web by a severing element. The invention also relates to an apparatus for carrying out the process.
In packaging technology, it is often necessary for packs, namely the (outer) wrapper thereof, to be provided with printing or some other marking. In the production of cigarette packs or multipacks for cigarettes, there is often a need for data concerning the time and place of production to be provided, in the region of the packaging machine or following the same, by corresponding printing on the packaging material, in particular on an outer wrapper for multipacks. A suitable printing unit is used for this purpose.
The marking or printing is to be provided on a precise location of the wrapper. It is thus necessary for the printing unit to be controlled correspondingly, namely to be actuated such that the printing is provided at the envisaged position.
The object of the invention is to provide measures which ensure precise positioning of the printing or some other marking on a blank for a pack, in particular multipack.
In order to achieve this object, the process according to the invention is characterized by the following features:
a) the markings or printing are/is provided on a continuous material web for the production of blanks during temporary storage of the material web, which is otherwise transported continuously,
b) the positioning of the markings or printing can be controlled by a printed-mark reader which detects printed marks on the material web,
c) detected incorrect positioning is compensated by relative movement between the printing unit and material web.
In the case of the process according to the invention, the correct position of the printing is thus ensured by markings on the material web being sensed and, in the case of any incorrect positioning, the material web is preferably moved in the conveying direction or counter to this during the stoppage phase to such an extent that the printing unit applies the printing at the precise predetermined position.
In the case of the process according to the invention, incorrect positioning of the material web relative to the marking element or relative to the printing unit is thus established and compensated by relative movement, in particular by the virtue of the material web being drawn forwards or back.
The apparatus according to the invention is characterized in that a printed-mark reader is assigned to the marking element or printing unit and is arranged upstream thereof, in the conveying direction. This printed-mark reader checks the correct positioning of the material web during the marking operation, that is to say during the temporary stoppage. Any adjustment movements of the material web are compensated by a pendulum mechanism for the web in conjunction with a rearward-conveying drive for the web.
Further details of the process and of the apparatus are explained in more detail hereinbelow with reference to drawings, in which:
FIG. 1 shows an apparatus for producing blanks as part of a packaging machine,
FIG. 2 shows a perspective illustration of a schematically illustrated material web with printing unit,
FIG. 3 shows an illustration analogous to FIG. 2 with movement compensation for the material web,
FIG. 4 shows an illustration corresponding to FIG. 3 with different relative positioning of the material web.